SalzundPfeffer

Doing my first timing belt change on an '84. I got ahead of myself and forgot to install the flywheel lock before I pulled everything to do the front seals. So, I'm manually setting the timing.

I can see the timing mark on the flywheel from the top of the engine. And I can see the timing marks on the camshaft and rear housing. So, I know where the cam is in relation to the crank.

Problem is, when I go to install the belt, it seems like I am about 1/2 tooth off on the timing when everything is tight. When I rotate the engine manually clockwise, the flywheel mark is indicating TDC and the cam sprocket is about a half a tooth from the camshaft timing mark.

I adjusted the belt forward and backward one tooth and same result. I was expecting everything to be dead nuts but is this close enough? Obviously nothing is hitting anything when I rotate it manually but I'm concerned the engine might not run optimally if the timing isn't exact. I'm using Arnnworx tensioning tools.

Thanks in advance,
-bp

Fara

to clarify, when setting the timing, is the slack in the belt on the top of bottom of the cam sprocket?

krystar

1/2 tooth off is somewhat normal. if u keep the cam sprocket stationary with belt just detensioned, u can try rocking the crank back and forth and get the crank timed up to take up the slack in the belt.

SalzundPfeffer

Basically, since I forgot to use the flywheel lock, I have a clamp on the cam, so its position is fixed. I then have been moving the belt back and forth one tooth on the crank sprocket. I then retension everything and spin the engine clockwise two revolutions and evaluate the timing. I line the cam sprocket up with the mark and then check the flywheel. Always appears to be 1/2 tooth off.

Do I need to instead make the adjustment on the cam sprocket rather than the crank sprocket?

Also, what is the engine's natural direction of rotation as I am looking at the car from the front? I assume it is clockwise.

-bp

968 GUY

Clockwise is correct.
Half a tooth may be a degree. After the belt stretches a bit, timing may change more.

divil

Are you looking at the flywheel mark from directly above? It's difficult to get in a position to look directly down, but otherwise it's always going to look a little off. Even the photo on Clark's Garage shows a slight misalignment due to the angle.

Also note in that Clark's article he explains another way to check the flywheel - it doesn't look any more accurate but it might be a help to combine the 2 methods. At the end of the day you cannot adjust the timing by less than 1 tooth on this car...so when everything else is lined up, I think the nearest 1/2 tooth has to be right.